Device for tensioning bundling straps



Oct. 27, 1964 a. c. BAILEY 3,154,114

DEVICE FOR TENSIONING BUNDLING STRAPS Filed Dec. 28, 1962 Mia! l #3 INV EN TOR.

George C Bailey ATTOR/VEK United States Patent M 3 154 114 DEVICE ron TENSICNING nUNnLmc STRAPS George C. Bailey, East Orange, N.J., assignor to The Thomas & Betts (30., Incorporated, Elizabeth, N.J., a

corporation of New Jersey Filed Dec. 28, 1962, Ser. No. 248,156 Claims. (Cl. 140-406) The present application is an improvement over the structure disclosed in application Serial Number 202,013, filed June 12, 1963.

The invention relates to devices for tensioning and locking tie straps or the like and more particularly to an improved hand tool adapted for tensioning a flexible, plastic strap after it has been looped about a plurality of articles disposed in bunched parallelism, and for thereafter maintaining the strap under tension while the tool is actuated toward closed position to twist the engaged free end portion of the strap relative to its looped portion whereby to align and lock or otherwise secure the strap upon itself against reverse movement and, at the same time, to perform a severing operation on the twisted free end portion of the strap.

More specifically, the invention resides in the herein described improvements in a hand tool of the parallel action pliers type, as shown in application Serial Number 202,013, which is particularly adapted for tensioning, locking and severing individual bundling straps of the character disclosed in US. Patent 3,022,557, whereby the application of such straps on a plurality of bunched insulated electric wire conductors, for example, may be eifected at spaced points therealong without difficult manipulation of the tool, as heretofore, and thus with greater convenience and dispatch and, with all tied straps under equal tension.

Heretofore, in tieing such bundling straps with the hand tool shown in application Serial Number 202,013, it was necessary to bring the strap manipulating plate elements on the jaws thereof, into a predetermined overlapping position, relative to the engaged body portion of the strap, solely by the operators skill or practice with the tool, and so hold the tool while turning it through an angle of 90 degrees, relative to the strap, to turn the engaged body portion thereof into alignment with a pair of aligned slots extending centrally across the eyelet in the head end portion thereof and lengthwise of the strap, for the purpose of securing the looped portion of the strap against reverse movement after being drawn taut about a plurality of bunched wire conductors.

The aforesaid hand tool, however, possessed a certain disadvantage in that the tool had to be turned through an angle of 90 degrees, relative to the strap, to turn the engaged flat body portion thereof into alignment with the aligned slots in the head end portion thereof. Thus, such turning of the tool through an angle of 90 degrees required time and considerable skill on the part of an operator, in addition to the time required subsequently to release the jaws of the tool to cut-off position.

Accordingly, it is an object of the invention to provide an improved hand tool of the character described whereby the above noted disadvantage is obviated.

A further object of the invention is to provide a hand tool of the character described whereby an inexperienced operator can tie an even larger number of bundling straps in less time with the same efficiency than was formerly possible with the hand tool of application Serial Number 202,013, in the hands of an experienced operator.

Another object of the invention is to provide an improved hand tool of the character described whereby thereof with said tool.

3,154,114 7 Patented Get. 27, 1964 A further object of the invention is to provide an improved hand tool of the forged steel type wherein the integral jaws thereof are offset at a small angle to the longitudinal center of the tool for the lateral or sidewise reception of a plastic bundling strap therebetween.

Another object of the invention is to provide an improved hand tool as described, wherein movement of the jaw members toward each other to a predetermined preset position is controlled automatically by means adapted to be released by an operator to effect a strap severing operation after the same has been twisted and secured against reverse movement.

A further object of the invention is to provide improvements in a hand tool of the character described whereby the tool is adapted to automatically twist an engaged portion of a looped bundling strap of flexible fiat plastic material normal to its looped portion upon movement of its jaw members toward closed position.

With the above and other objects in view, the invention resides in the novel construction, combination, and arrangement of parts, the novel features of which are set forth with particularity in the appended claims, the invention itself, however, both as to its organization and method of operation, together with additional objects and advantages thereof, being best understood from the following description of a specific embodiment thereof, when taken in connection with the accompanying drawing in which:

FIGURE 1 is a perspective view of the improved hand tool illustrating the manner in which the engaged free end portion of a looped strap, including its apertured head end, is received between the open jaws of the tool preparatory to initially twisting or turning its engaged end portion while drawing the strap taut;

FIGURE 2 is a plan View showing the hand tool in FIGURE 1, after its jaws have been moved toward closed position to initially twist the engaged strap end portion normal to its looped portion while drawing the same taut;

FIGURE 3 is a similar view showing the jaws of the hand tool in FIGURES 1 and 2, after the jaws have been released for movement to closed position in which operation the entire engaged end portion of the strap is turned or twisted normal to its looped portion whereby to lock or secure the strap upon itself against reverse movement and to subsequently sever the engaged free end portion from its secured looped portion;

FIGURE 4 is a partial top plan view of the improved hand tool shown in the preceding figures, illustrating the angularly ofiset jaw members with respect to the longitudinal center line of the tool, and the free end portion of a looped bundling strap disposed between the jaw members at an angle to said longitudinal center line;

FIGURE 5 is a fragmentary front end view of the respective jaw members of the tool illustrating the manner in which a strap is initially received in the upper jaw preparatory to turning or twisting its engaged end portion upon movement of the jaw members toward closed position;

FIGURE 6 is a fragmentary, tranverse sectional view, taken on the line 6-6 of FIGURE 5;

FIGURE -7 is a similar fragmentary sectional view illustrating the position of the jaws after they have been moved to closed position in which position the free end portion of the strap is severed from its looped portion and the free end of the looped portion finally twisted substantially normal thereto for locking the same against reverse movement in the head end of the strap; and

FIGURE 8 is a fragmentary perspective view illustrating the ends of the jaw members as moved in part toward closed position.

Referring to the drawing, the invention resides in a hand tool of the pliers type, generally indicated at 10,

comprising a pair of crossed handle members 12, of forged steel pivotally connected as at 14, in accordance with the Pivoted Tool Joint Construction disclosed in Porter Patent No. 2,920,927, said handle members including a pair of jaws 16, of rectangular cross section formed integral therewith and adapted to swing in an arc in scissors fashion when moved toward each other upon angular manipulation of said handle members. As best shown in FIGURE 2, the jaws 16 and pivoted handle members 12 are yieldably maintained in open or spaced apart position by means of a coiled compression spring 18 disposed between the opposed inner faces of the handle members 12 adjacent the pivotal connection 14, with each of its opposite ends seated in a suitable recess or cavity formed in the inner faces of the respective handle members 12, by means of a drill or the like, the hand grip portion of the handle members 12 being provided with a plastic covering or sleeve 20, whereby to insulate a portion of the tool 10 and at the same time provide a non-slip surface thereon.

In accordance with the invention and as best shown in FIGURES 1 through 4, a major portion of the respective jaws 16 extending beyond the fulcrum or pivotal connection 14, between the handle members 12 is offset or bent to the left or toward the bottom of the sheet, as at 22, in FIGURE 4, and then in the opposite direction, as at 24, to extend at a small angle toward the longitudinal center line 26, through the handle members 12, whereby the jaws 16 are so offset with respect to said handle members that a bundling strap S may be positioned between the jaws 16, sidewise in angular offset relation to the pivotal connection 14, as well as longitudinally of the jaws 16, from the nose end thereof rearwardly in spaced angular relation to the handle members 12.

Further in accordance with the invention, the lower jaw 16 terminates at its nose end in an integral right angular extending lip 28, in opposed relation to the nose end of the opposite or upper jaw 16, and its free end provided with a small angular rake or clearance along its transverse edge 30, having a small, arcuate notch 32 centrally of its width adapted to provide clearance for a ribbed, arcuate face 34 of the strap S. The lower jaw 16 is further provided with an upstanding cutting blade 36, suitably secured against the inner face of the lip 28, as by means of a screw or the like, the blade 36 extending slightly beyond the end of the lip 28 with its free end provided with an angular rake forming a transverse knife edge 38, in spaced parallelism with the transverse edge of the lip 28 as and for the purpose hereinafter described.

The upper or opposite jaw 16 has its working face 40 shortened at the nose end thereof to form a transverse shoulder 42 thereon, and to provide clearance for purposes presently to be described. The upper jaw 16 is further provided at its nose end with an angle bracket 44, having one leg thereof secured on the top face thereof by means of suitable screws 46, or the like, the opposite leg 48 of the angle bracket 44 extending across the nose end thereof at right angles to the opposed faces of the respective jaws 16, and in partial overlapping sliding contact relation with the lip 28 on the lower jaw 16, when the jaws of the tool are in the position shown in FIG- URES 2 and 3.

As best shown in FIGURES and 8, a portion of the extended leg 48 of the angle bracket 44 is reduced in thickness to form a transverse shoulder on its under side adjacent the juncture between its opposite legs to provide a transverse shearing edge 50, in alignment with the transverse knife edge 38 of the cutter blade 36 secured to the lower jaw 16 when the respective jaws are moved toward closed position.

Further in accordance with the invention, the extended free leg 48 of the angle bracket 44 terminates in a hook like end portion 52 by virtue of a rectangular aperture 54 therethrough and a slot 56 extending from one corner of said aperture and separating one edge of said end pertion 52 from the leg 48, proper to provide a side entrance passage to said aperture 54, as best shown in FIGURE 5, whereby a strap S may be inserted sidewise into said aperture 54, instead of axially endwise thereof. The outer face of the extended free leg 48, of the angle bracket 44 is further provided with an elongated recess 58, extending lengthwise thereof at an angle of 5 degrees, for example, to its marginal edges, and open at one end for ease in machining the recess therein, the recess 58 extending across the rectangular aperture 54 through said free leg 48 into the inner side of the hook like end portion 52 to provide a small continuation of the floor 60 of said recess in said end portion 52, whereby said recess 58 is adapted to receive and support the oval head end portion of the strap S, therein as best shown in FIGURES 6 and 7. The distance across the defining side margins of the rectangular aperture 54, as seen in FIGURE 5, being less than the width of the body portion of the strap S, whereby the strap is frictionally held against reverse movement relative to the jaws 16 of the tool 16 during the following operations thereon to render the strap taut by means now to be described.

Further in accordance with the invention, and as best shown in FIGURES 1 through 3, means for drawing a strap S taut about a plurality of bunched parallel linear elements E, in small successive increments of adjustment comprises an arcuate pawl 62, provided with a pair of spaced parallel ears depending from one end thereof and suitably apertured to serve as hinge members, the pawl being thereby pivotally mounted across the inner or working face of the lower jaw 16, as viewed in the drawing, adjacent its nose end by means of a transverse hinge pin 64 extending through said ears and lower jaw 16, as shown in section in FIGURE 2. The pawl 62 is yieldably biased into substantially upright position by means of a suitable spring 66 mounted on the hinge pin 64 with one of its ends bearing on the underside of the pawl 62, and its opposite end bearing on the bottom of a rectangular clearance recess or cavity, formed in the inner face of the lower jaw 16 whereby the pawl 62 is adapted for limited angular movement between the opposing faces of the jaws 16, toward the fulcrum 14 of the tool 10 from a normal upright position to a substantially horizontal position.

As shown in FIGURES l, 2, and 3, the convex face of the pawl 62 is suitably abraded, knurled, serrated or the like as at 68, whereby the pawl 62 is adapted to bite or grip the body of the strap S, in response to repeated movement of the jaws 16 toward each other as when drawing a looped bundling strap taut.

Further in accordance with the invention and as best shown in FIGURES 1, 2 and 3, movement of the jaws 16 toward each other is limited by a spring biased detent lever 70, pivotally mounted on the straight rear portion of the upper jaw 16 by means of a suitable pivot pin 72. The detent lever 70 comprises a U-shaped end portion in cross section, wherein one side terminates in a detent finger 74, depending beyond the inner face of the upper jaw 16 into close proximity to the rear end of the working face of the lower jaw 16, and a finger piece control member 76 extending from its pivoted end portion partly over one of the handle members 12. As shown in FIG- URES 1, 2 and 3, the detent lever 70 is biased into operative position by means of a small coiled spring 78 having one end thereof suitably seated on the upper jaw 16 with its opposite end acting against the under side of its pivoted portion. Thus, when the respective jaws 16 are moved toward each other, the detent finger 74 of the pivoted lever 70, normally in the path of the working face of the lower jaw 16, is brought into engagement therewith as the knife edge 38 of the blade 36 carried by the lower jaw 16 approaches the transverse shearing edge 38 on the extended free leg 48 of the angle bracket 44 mounted on the upper jaw 16, whereby a severing operation on an engaged end portion of a looped bundling strap S, in response to movement of the respective jaws 16 is precluded until the finger piece '76 of the pivoted detent lever 70 is depressed to release the jaws 16 for further movement toward each other as exemplified in FIGURE 3.

In view of the foregoing, when considered in the light of the accompanying drawing, it will be clear that the present invention provides a forged, solid frame hand tool of the pliers type wherein the jaws are offset or bent at an acute angle to the longitudinal center of said tool and to one side thereof as best seen in FIGURE 4, whereby the insertion of the tail end of a looped strap S between the jaws 16 sidewise, will pass rearwardly to one side of the fulcrum 14 of the tool as the strap is drawn through the jaws. It will also be clear that the nose end of the upper jaw 16 includes an angle plate suitably secured thereto with one leg thereof extending normal thereto and provided with an apertured and recessed hook-like end portion including an open ended slot therebetween for receiving the extended free end portion of a looped strap therebetween in a plane substantially normal to the opposed working faces of the respective jaws 16, as in FIGURE 5.

With the engaged portion of the strap S between the jaws 16, as noted above, movement of the jaws 16 toward each other causes the pivoted pawl carried by the lower jaw to engage the outer margin of the strap, as in FIGURE 1, whereby the engaged portion of the strap S is turned over or twisted, relative to its looped portion, with its flat face or side in abutment with the working face 40 of the upper jaw 16, as shown in FIGURE 2. In this position of the strap S, movement of the jaws 16 toward and away from each other causes the pawl on the lower jaw 16 to draw the looped strap taut, reverse movement of the engaged portion'of the strap S being precluded by the snug fit thereof in the apertured free end of the angle plate secured on the upper jaw 16.

With the engaged portion of the strap S, twisted as in FIGURE 2, further movement of the jaws 16 toward each other causes an integral, right angular lip on the nose end of the lower jaw 16, presenting a slightly inclined transverse edge having an arcuate notch centrally thereof to push against the partly twisted portion of the strap S, as in FIGURE 6, to complete the twist as in FIGURE 7, whereby to lock the looped portion of the strap S upon itself. At the same time that the right angular lip extension on the lower jaw 16 completes the twist in the engaged portion of the strap automatically in response to movement of the respective jaws toward each other, a cutter blade secured to and against the inner wall of the lower jaw lip and presenting a transverse knife edge, causes the free end portion of the strap S to be severed from its looped portion in the manner best illustrated in FIGURE 3. Horeover, it will be seen in FIGURE 8, that the arcuate notch centrally of the transverse edge presented by the right angular lip extension on the lower jaw 16 serves to guide, turn and hold the engaged portion of the strap S, whereby the means carried by the respective jaw 16 automatically lock the strap upon itself against reverse movement by twisting its engaged portion into a plane normal to its looped portion.

-on the upper jaw 16 for automatically limiting movement of the respective jaws toward each other to prevent severing the engaged portion of the strap S, while the jaws are initially moved toward and away from each other to cause the pivoted pawl on the lower jaw 16 to draw the strap S taut by successive grips thereon, the detent means being subsequently released to permit full movement of the respective jaws 16 toward each other as illustrated in FIGURE 3.

While the invention has been illustrated and described with respect to one embodiment thereof, it is to be expressly understood that various changes and modifications may be made therein without departing from the inventive concept underlying the same. Therefore, the invention is not to be limited except as is necessitated by the prior art and the scope of the appended claims.

What is claimed is:

1. A hand tool adapted for tensioning, twisting and severing a looped flexible strap comprising a pair of jaw members presenting flat, opposed working faces movable toward and away from each other in response to a pair of integral, spring biased handle members, said jaw members being provided respectively with means for laterally receiving and linearly guiding a tail-end portion of a looped bundling strap between said jaw members in a plane substantially normal to the working faces thereof, means mounted on one of said jaw members for engaging the outer marginal edge of the engaged end portion of said strap and twisting the same with its uppermost face in abutment with the working face of the other of said jaw members, and for completing the twist in the engaged end portion of said strap to a point adjacent said first named means and for severing the engaged end portion of said strap from its looped portion upon movement of said jaw members toward each other into overlapping relation.

2. The invention set forth in claim 1, characterized further in that said second named means is provided with a transverse edge having an arcuate notch centrally thereof for accommodating the contour of one face of said looped strap whereby the engaged end portion of said strap is held centrally between said jaw members.

3. The invention set forth in claim 1, characterized further in that a detent means is pivotally mounted on one of said jaw members for initially limiting movement of said jaw members toward each other and manually operable for subsequently releasing said jaw members for movement toward each other to cut-off position.

4. A hand tool of the character described wherein a pair of rectangular jaw members present fiat, opposed working faces, one of said jaw members being provided at its nose end with angular means adapted for receiving and guiding a tail end portion of a looped, flexible strap between said jaw members in a plane substantially normal to the working faces thereof, means pivotally mounted on the working face of the opposite jaw member including a biasing means adapted upon limited movement of said jaw members toward each other to engage the outer marginal edge of the engaged end portion of said strap and partially twist the same whereby its upper face is brought into abutment with the working face of the first named jaw member while drawing the same taut, and angular means including a cutting blade provided on the nose end of the said opposite jaw member adapted respectively upon total movement of said jaw members toward each other to complete the twist in the engaged portion of said strap to a point adjacent said first named means and to coact with a shearing means thereon for substantially simultaneously severing the engaged end portion of said strap from its looped portion.

5. A hand tool of the character described wherein a pair of opposed jaw members present fiat, parallel working faces, one of said jaw members being provided at its nose end with means for inserting a tail end portion of a looped, flat, flexible strap between said jaw members in a plane normal to the working faces thereof, means mounted intermediate the working face of the opposite 7 jaw member adapted upon movement of said jaw members toward each other to engage the outer marginal edge of the inserted portion of said strap and partially twist the same into abutting parallelism with the working face of the first named jaw member, and means disposed in contacting relation provided on the nose end of the said opposite jaw member adapted respectively upon total movement of said jaw members toward each other to complete the twist in the engaged portion of said strap to a point adjacent said first named means and substantially simultaneously severing the tail end portion of said strap from its looped portion.

6. The invention set forth in claim 4, characterized further in that said angular means provided on the nose end of the opposite of said jaw members comprises an integral lip extending normal thereto in opposed relation with the other of said jaw members, said integral lip having an arcuate notch centrally of its transverse edge, and a cutter blade secured to and in abutment with the inner face of said integral lip presenting a knife edge extending slightly beyond the transverse edge of said integral lip, said other of said jaw members being provided with a shearing edge in alignment with said knife edge when said jaw members are moved into overlapping relation with each other to bring said lip into engagement with the partially twisted portion of said strap to complete the twisting thereof to its looped portion to sever the twisted end portion therefrom.

7. A hand tool comprising a pair of jaw members pivotally connected for movement toward and away from each other upon movement of a pair of integral, spring influenced handle members, said jaw members being formed at an acute angle to the longitudinal center of said tool and disposed to one side of said center, angular means provided on the nose end of each of said jaw members and extending normal thereto in opposed coactable relation adapted respectively for receiving an extended end portion of a looped flexible plastic strap between said jaw members from one side thereof and in a plane substantially normal to the opposed working faces thereof, and means pivotally mounted on one of said jaw members including a biasing means adapted for engaging one marginal edge of said extended end ortion of said looped strap whereby to partially twist the same into the plane accupied by the opposed working faces of said jaw members and to draw the same taut upon partial movement of said jaw members toward each other, and means carried by the other of said jaw members including a shearing means adapted respectively for completing the twist in the engaged end portion of said strap to a point adjacent its looped portion and for simultaneously severing said twisted end portion therefrom upon total movement of said jaw members toward each other.

8. The invention set forth in claim 7 characterized further in that said angular means provided on the nose end of one of said jaw members comprises an angle bracket secured to said jaw member with its free leg extending across the nose end thereof and provided with a rectangular aperture therethrough and an open ended slot in communication therewith adapted for receiving the body portion of a flexible plastic strap in a plane substantially normal to the opposed working faces of said jaw members and to one side outwardly thereof.

9. A hand tool adapted for tensioning, twisting and severing a looped'bundling strap comprising a pair of pivoted jaw members presenting flat, opposed working faces movable toward and away from each other in response to movement of a pair of integral, spring biased handle members, angular means including a cutting means secured on the nose end of one of said jaw members adapted for receiving and guiding a tail end portion of a looped plastic strap between said jaw members in a plane substantially normal to the working faces thereof, means pivotally mounted on the opposed jaw member including a biasing means adapted upon movement of said jaw members toward each other to engage the outer marginal edge of the engaged end portion of said strap and to twist the same into the plane of and into abutment with the working face of said first named jaw member while tensioning said strap, angular means integral and extending normal to the nose end to the opposite jaw member adapted to be brought into overlapping relation with said first named angular means for completing the twist in said engaged strap portion to a point adjacent said first named angular means upon overlapping movement of said jaw members, and a cutting means secured to said second named angular means adapted to engage the transverse knife edge on said first named angular means in shear upon total movement of said jaw members toward each other to cut-01f position.

10. A hand tool of the character described wherein a pair of pivoted rectangular jaw members present flat, opposed working faces, the working face of one of said jaw members terminating in a transverse shoulder short of its nose end, angular means secured on said one jaw member extending across its nose end, said angular means being provided with a transverse knife edge and a reotangular aperture including an open ended slot in communication with said aperture, adapted for receiving and guiding a tail end portion of a looped flexible strap between said jaw members in a plane substantially normal to the working face of said first named jaw member, means pivotally mounted on the working face of the opposite jaw member adapted upon partial movement of said jaw members toward each other to engage the outer marginal edges of the engaged end portion of said strap and partially twist the same whereby its uppermost face is brought into abutment with the working face of said first named jaw member while drawing the same taut, angular means integral with and extending normal to the nose end of said opposite jaw member adapted to be brought into overlapping relation with said first named angular means for completing the twist in the tail end portion of said strap upon movement of said jaw members toward each other, and a cutting means secured to said second named angular means adapted to engage the knife edge on said first named angular means in shear upon total movement of said jaw members toward each other, and a detent lever pivotally mounted on one of said jaw members for limiting movement of said jaw members toward each other including means for manually releasing said jaw members for total movement toward each other to cutoff position.

References Cited in the file of this patent UNITED STATES PATENTS 2,681,504 Fox June 22, 1954 2,882,934 Gerrard Apr. 21, 1959 3,047,945 Logan Aug. 7, 1962 

1. A HAND TOOL ADAPTED FOR TENSIONING, TWISTING AND SEVERING A LOOPED FLEXIBLE STRAP COMPRISING A PAIR OF JAW MEMBERS PRESENTING FLAT, OPPOSED WORKING FACES MOVABLE TOWARD AND AWAY FROM EACH OTHER IN RESPONSE TO A PAIR OF INTEGRAL, SPRING BIASED HANDLE MEMBERS, SAID JAW MEMBERS BEING PROVIDED RESPECTIVELY WITH MEANS FOR LATERALLY RECEIVING AND LINEARLY GUIDING A TAIL-END PORTION OF A LOOPED BUNDLING STRAP BETWEEN SAID JAW MEMBERS IN A PLANE SUBSTANTIALLY NORMAL TO THE WORKING FACES THEREOF, MEANS MOUNTED ON ONE OF SAID JAW MEMBERS FOR ENGAGING THE OUTER MARGINAL EDGE OF THE ENGAGED END PORTION OF SAID STRAP AND TWISTING THE SAME WITH ITS 